Background: Alterations in the cellular biological responses were examined in a series of LNCaP human prostate tumor cells growing under different conditions.
Materials and methods: LNCaP cells were grown in two-dimensional monolayer cultures, three-dimensional spheroids, or as solid tumors in immune-deprived mice.
Results: As compared with the growth in the monolayers, cell growth in the spheroids was reduced, while VEGF production was increased. Immunohistochemical analysis of the spheroids revealed that cells showing Ki-67 up-regulation were localized in the peripheral layer, and that the central core was necrotic. The gene expression profile in the solid tumor tissue was obviously different from that in the monolayers; however, it was similar to that in the spheroids. The prostate-specific antigen levels in the culture supernatants of spheroids increased with time and decreased with anticancer agent treatment.
Conclusion: Spheroid formation from human prostate tumor cells exhibits tissue-like features.